Radiations such as X-rays, gamma rays, and neutron beams are generated in a micro region where a nuclear fusion occurs. By utilizing this phenomenon, dot-like radiation sources are provided. Therefore, apparatus which generate various radiations by irradiating fuel particles which are fusion fuels with lasers have been under study.
An example of such radiation generating apparatus is one which generates neutrons by using a high-intensity proton accelerator. There is also an apparatus which generates neutrons by irradiating a thin plastic film, whose hydrogen is replaced with deuterium, with laser light. Further, there is an apparatus which generates high-energy protons by irradiating a hydrogen-containing particle or thin film with laser light.
Patent Literature 1 discloses an apparatus which generates neutrons. As a fusion fuel, this apparatus uses a microdroplet formed by liquid deuterium. First, in the apparatus, liquid deuterium is jetted from a nozzle, so as to produce a droplet of liquid deuterium. The droplet is irradiated with infrared laser light, so as to explode into microdroplets. The microdroplets are irradiated with a femtosecond pulse laser, so as to be ionized, and the resulting ions are caused to collide with each other, so as to generate neutrons.